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Topic: Carb numbering (Read 4312 times)

The carburetor on my 69 is numbered 702 (60's production) 9 (year produced) 2 (quadrajet) 0 (Chevrolet) 7 (manual Trans). However the date on the carb is 3477 which I read as the 347th day of 67, can anyone tell me why the seeming discrepancy and if this carb is original to my 69 350/300 SS?

The 7029207 carb was used on the 69 Corvette 350/350 with manual transmission, so it's not original to your car. I would also bet it's an over the counter service replacement dated the 347th day of 1977.

Yeah, for some reason Rochester pumped out a TON of those carbs for service replacement requirements. Do a search on ebay for 7029207 and you'll find lots of over the counter, early to late 70's dates. I have one on a 396 in my garage that was assembled the 83rd day of 1972. My theory is that they may have used this carb for multiple applications in a service environment, but of course, that's just a theory.

For the 1969 Corvette, a total of 12,846 L46 (350/350) cars were sold (no breakdown of auto -vs- manual), but there sure seems to be a ton of service carbs for this engine!

Okay, my theory was right. I conversed with John (Hinckley), and probably one of the foremost authorities on Corvettes, Joe Lucia, and Joe said that yes, "the GM #7029207 carburetor was used for many years as the service carburetor for ALL 1968-69 small blocks".

So I guess this is why you can't swing a dead cat without hitting one of those things!

Timm I installed the "07029207" service replacement unit in 1983 when I wanted to rebuild my original 7029203 but was unsure of my skills never having rebuilt a carburetor and still needed to drive to work every day.

The Zero preceding the 7029207 indicated it was a service replacement. As my Uncle who was a life long GM parts manager explained it - GM always streamlined the parts supply by selecting best of bread parts to assume replacement roles at the end of each model year for multiple divisions and platforms when ever possible. Often one survivor part would become the service replacement, until a special universal designed part would be phased in a few years down the road if demand continued.

The added benefit of the Corvette 7029207 Rochester Quadrajet being selected as the service replacement for all 1969 Chevrolet 350 small blocks is that it kept the original 7029207 jetting standards which were slightly more aggressive than the original jetting in the 7029203 that was on my 350/300 L48.

As fate would have it now 30 years later and 20 years in storage I need to rebuild that same 07029207 so finally I'm rebuilding the original 7029203 that has been waiting since 1983 for a rebuild. I'll do them both and if I screw it up I have a brand new shrink wrapped in the Delco box 07029207 in storage just in case

Carb Junkies ( http://www.carbjunkys.com/ ) rebuilt mine and did it using the same finish as the original parts, specifically the butterfly and choke flaps. Most resto shops dichromate everything including the flaps but mine have silver zinc color secondary butterfly and choke flaps with the dichromate body and other parts. That was important to me to retain the correct finish. Turn around time as about 18 days and cost very reasonable (I think it was $325 thereabouts).

I too, have a 7029207 Q-jet on my L48 '69. When I bought my car in '79, it appeared to be a virtually untouched original and because of that, I never checked numbers on any of the components until this year (crazy,I know). Most of my number verification efforts are spent on my big block car. The carb has a May '69 date, I believe, and the car itself is a 4th week of November '68 Norwood model. I assumed the carb was replaced under warranty and this post gives some creedence to that idea. I suppose it could have been replaced in '79 just prior to my purchase (Nov.'79). Is there anyway to distinguish dates '69 vs '79?

Somewhere in the early 70s (I think 1972) Holley carbs went from a 3 digit date to a 4 digit date. For a 4 digit date code, the first 3 characters represented the Julian date (1 through 366) and the last character represented the year of the decade.

3 digit date codes were prior to about 1972, and I believe the digits were for year, month, week.

It is possible your was replaced during the recall for the Hot Slot carb fire issue. When you remove the carb next look and see if the slot in the manifold was filled or the ends fitted with plugs. That would most likely be why you have the service dated so close.

Somewhere in the early 70s (I think 1972) Holley carbs went from a 3 digit date to a 4 digit date. For a 4 digit date code, the first 3 characters represented the Julian date (1 through 366) and the last character represented the year of the decade.

3 digit date codes were prior to about 1972, and I believe the digits were for year, month, week.

Sorry,bcmiller, I was wondering about Q-jets. That was the carb in OP reference. I am aware about Holley's and dating changes.